linux: add support for numa set_mempolicy(2)

mempolicy.c:
- new file
- add CPP info to match userland vs kernel interface versioning to avoid
  manual tracking of numaif interface
- provides libcrun_set_mempolicy as wrapper to set_mempolicy(2) with all
  possible error checking and report that can be done before calling
  set_mempolicy(2).
- use libnuma nodemask parser that is actively maintained by numa kernel
  maintainers to match kernel features and provides accurate error
  reports based on hw running the code (see also changes to error.c)

mempolicy.h:
- new file
- define libcrun_set_mempolicy

mempolicy_internal.h:
- new file
- define memory policy mode and flags maps to be shared and updated
  in one single place
- numa python bindings are not available on most distros. This makes
  numa features detection challenging for crun test suite without
  causing false positives.
  This header provides shared common definitions with
  tests_mempolicy_helper.c that is used by the test suite and avoid
  duplicate code around

container.c:
- add call to libcrun_set_mempolicy in libcrun_container_run_internal

error.c:
- override numa_warn WEAK symbol from libnuma to capture numa parser
  errors and translate them into crun warnings

tests/tests_mempolicy_helper.c:
- new file
- print a list of numa features detected during the build
- shares info from mempolicy_internal.h

tests/test_mempolicy.py:
- new file
- add both negative and positive tests for mempolicy.c
- tests will run if hw supports numa or skip

Makefile.am:
- update
- changes verified also with make distcheck

Signed-off-by: Fabio M. Di Nitto <[email protected]>

Author: fabbione

Makefile.am

@@ -67,6 +67,7 @@ libcrun_SOURCES = src/libcrun/utils.c \
 		src/libcrun/linux.c \
 		src/libcrun/mount_flags.c \
 		src/libcrun/scheduler.c \
+		src/libcrun/mempolicy.c \
 		src/libcrun/seccomp.c \
 		src/libcrun/seccomp_notify.c \
 		src/libcrun/signals.c \
@@ -160,7 +161,7 @@ EXTRA_DIST = COPYING COPYING.libcrun README.md NEWS SECURITY.md rpm/crun.spec au
 	src/libcrun/custom-handler.h src/libcrun/io_priority.h \
 	src/libcrun/handlers/handler-utils.h \
 	src/libcrun/linux.h src/libcrun/utils.h src/libcrun/error.h src/libcrun/criu.h \
-	src/libcrun/scheduler.h src/libcrun/status.h src/libcrun/terminal.h \
+	src/libcrun/scheduler.h src/libcrun/mempolicy.h src/libcrun/mempolicy_internal.h src/libcrun/status.h src/libcrun/terminal.h \
 	src/libcrun/mount_flags.h src/libcrun/intelrdt.h src/libcrun/ring_buffer.h src/libcrun/string_map.h \
 	src/libcrun/net_device.h \
 	crun.1.md crun.1 libcrun.lds \
@@ -179,7 +180,7 @@ noinst_PROGRAMS = crun
 endif
 
 if BUILD_TESTS
-check_PROGRAMS = tests/init $(UNIT_TESTS) tests/tests_libcrun_fuzzer
+check_PROGRAMS = tests/init $(UNIT_TESTS) tests/tests_libcrun_fuzzer tests/tests_mempolicy_helper
 
 TESTS_LDADD = libcrun_testing.la $(FOUND_LIBS) $(maybe_libyajl.la)
 
@@ -212,6 +213,11 @@ tests_tests_libcrun_errors_SOURCES = tests/tests_libcrun_errors.c
 tests_tests_libcrun_errors_LDADD = $(TESTS_LDADD)
 tests_tests_libcrun_errors_LDFLAGS = $(crun_LDFLAGS)
 
+tests_tests_mempolicy_helper_CFLAGS = -I $(abs_top_builddir)/libocispec/src -I $(abs_top_srcdir)/libocispec/src -I $(abs_top_builddir)/src/libcrun -I $(abs_top_srcdir)/src/libcrun
+tests_tests_mempolicy_helper_SOURCES = tests/tests_mempolicy_helper.c
+tests_tests_mempolicy_helper_LDADD = $(TESTS_LDADD)
+tests_tests_mempolicy_helper_LDFLAGS = $(crun_LDFLAGS)
+
 endif
 TEST_EXTENSIONS = .py
 PY_LOG_COMPILER = $(PYTHON)
@@ -225,6 +231,7 @@ PYTHON_TESTS = tests/test_capabilities.py \
 	tests/test_hostname.py \
 	tests/test_limits.py \
 	tests/test_oci_features.py \
+	tests/test_mempolicy.py \
 	tests/test_mounts.py \
 	tests/test_paths.py \
 	tests/test_pid.py \

src/libcrun/container.c

@@ -23,6 +23,7 @@
 #include "container.h"
 #include "utils.h"
 #include "seccomp.h"
+#include "mempolicy.h"
 #ifdef HAVE_SECCOMP
 #  include <seccomp.h>
 #endif
@@ -2805,6 +2806,10 @@ libcrun_container_run_internal (libcrun_container_t *container, libcrun_context_
   if (UNLIKELY (ret < 0))
     return ret;
 
+  ret = libcrun_set_mempolicy (def, err);
+  if (UNLIKELY (ret < 0))
+    return ret;
+
   ret = libcrun_configure_handler (container_args.context->handler_manager,
                                    container_args.context,
                                    container,

src/libcrun/error.c

@@ -480,6 +480,23 @@ libcrun_warning (const char *msg, ...)
   va_end (args_list);
 }
 
+#ifdef HAVE_NUMA
+/* override libnuma internal numa_warn implementation
+ * that is defined as WEAK to allow consumers to define
+ * their own behavior.
+ * symbol has to be public for linker to use our version
+ * and allow to convert numa messages into libcrun messages */
+LIBCRUN_PUBLIC
+void
+numa_warn (int number arg_unused, char *msg, ...)
+{
+  va_list args_list;
+  va_start (args_list, msg);
+  write_log (0, LIBCRUN_VERBOSITY_WARNING, msg, args_list);
+  va_end (args_list);
+}
+#endif
+
 void
 libcrun_error (int errno_, const char *msg, ...)
 {

src/libcrun/mempolicy.c

@@ -0,0 +1,172 @@
+/*
+ * crun - OCI runtime written in C
+ *
+ * Copyright (C) 2017, 2018, 2019 Giuseppe Scrivano <[email protected]>
+ * crun is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation; either version 2.1 of the License, or
+ * (at your option) any later version.
+ *
+ * crun is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with crun.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <config.h>
+#include "linux.h"
+#include "utils.h"
+#include <ocispec/runtime_spec_schema_config_schema.h>
+
+#ifdef HAVE_NUMA
+#  include <numa.h>
+#  include <numaif.h>
+#  include "mempolicy_internal.h"
+
+#  define CRUN_NUMA_API_VERSION 2 /* numa.h LIBNUMA_API_VERSION at the time of writing */
+#  define CRUN_NUMA_MPOL_MAX 7    /* numaif.h MPOL_MAX at the time of writing */
+
+#  ifndef LIBNUMA_API_VERSION
+#    error "Unable to determine libnuma api version"
+#  else
+#    if LIBNUMA_API_VERSION > CRUN_NUMA_API_VERSION
+#      warning "This code was written with libnuma API version 2. numa.h reports a higher version"
+#    endif
+#  endif
+#  ifndef MPOL_MAX
+#    error "Unable to determine numaif interface version"
+#  else
+#    if MPOL_MAX > CRUN_NUMA_MPOL_MAX
+#      warning "This code was written with numaif MPOL_MAX 7. numaif.h reports a higher version"
+#    endif
+#  endif
+
+static int
+mpol_str2int (const char *str, const str2int_map_t *map)
+{
+  int idx = 0;
+
+  while (map[idx].name != NULL)
+    {
+      if (! strcmp (map[idx].name, str))
+        {
+          return map[idx].value;
+        }
+      idx++;
+    }
+
+  errno = EINVAL;
+  return -1;
+}
+#endif
+
+int
+libcrun_set_mempolicy (runtime_spec_schema_config_schema *def, libcrun_error_t *err)
+{
+#ifdef HAVE_NUMA
+  runtime_spec_schema_config_linux_memory_policy *memory_policy = NULL;
+  int mpol_mode = 0;
+  int mpol_flag = 0;
+  int mpol_mode_flags = 0;
+  struct bitmask *nodemask = NULL;
+  size_t i = 0;
+  int ret = 0;
+  int savederrno = 0;
+
+  libcrun_debug ("Initializing linux numa mempolicy");
+
+  if (def->linux && def->linux->memory_policy)
+    {
+      memory_policy = def->linux->memory_policy;
+
+      libcrun_debug ("Checking hardware numa availability");
+      if (numa_available () < 0)
+        {
+          return crun_make_error (err, ENOENT, "linux numa not supported on current hardware");
+        }
+
+      libcrun_debug ("Validating linux numa mempolicy");
+
+      /* validate memory policy mode */
+      if (! memory_policy->mode)
+        {
+          return crun_make_error (err, EINVAL, "linux numa mempolicy mode is missing from the configuration");
+        }
+      libcrun_debug ("Validating mode: %s", memory_policy->mode);
+      mpol_mode = mpol_str2int (memory_policy->mode, mpol_mode_map);
+      if (mpol_mode < 0)
+        {
+          return crun_make_error (err, EINVAL, "Requested linux numa mempolicy mode '%s' is unknown", memory_policy->mode);
+        }
+      mpol_mode_flags = mpol_mode;
+
+      /* both MPOL_DEFAULT and MPOL_LOCAL calls to set_mempolicy expects only
+       * the mpol_mode, no nodemask or flags */
+      if (mpol_mode != MPOL_DEFAULT && mpol_mode != MPOL_LOCAL)
+        {
+          /* validating memory policy flags */
+          libcrun_debug ("Validating mode flags: %zu configured", memory_policy->flags_len);
+          for (i = 0; i < memory_policy->flags_len; i++)
+            {
+              libcrun_debug ("Validating mode flag: %s", memory_policy->flags[i]);
+              mpol_flag = mpol_str2int (memory_policy->flags[i], mpol_flag_map);
+              if (mpol_flag < 0)
+                {
+                  return crun_make_error (err, EINVAL, "Requested linux numa mempolicy flag '%s' is unknown", memory_policy->flags[i]);
+                }
+              mpol_mode_flags = mpol_mode_flags | mpol_flag;
+            }
+
+            /* sanity check mode and flags combinations */
+#  if defined MPOL_F_NUMA_BALANCING
+          if ((mpol_mode_flags & MPOL_F_NUMA_BALANCING) && mpol_mode != MPOL_BIND)
+            {
+              return crun_make_error (err, EINVAL, "Requested linux numa mempolicy flag MPOL_F_NUMA_BALANCING is incompatible with %s", memory_policy->mode);
+            }
+#  endif
+#  if defined MPOL_F_RELATIVE_NODES && defined MPOL_F_STATIC_NODES
+          if ((mpol_mode_flags & MPOL_F_RELATIVE_NODES) && (mpol_mode_flags & MPOL_F_STATIC_NODES))
+            {
+              return crun_make_error (err, EINVAL, "Requested linux numa mempolicy flag MPOL_F_RELATIVE_NODES and MPOL_F_STATIC_NODES cannot be combined");
+            }
+#  endif
+          /* validate memory nodes */
+          if (! memory_policy->nodes)
+            {
+              return crun_make_error (err, EINVAL, "linux numa mempolicy nodes is missing from the configuration");
+            }
+          libcrun_debug ("Validating nodes: %s", memory_policy->nodes);
+          /* validation is done by libnuma based on hw environment
+           * and numa_warn symbol is overridden in error.c to convert
+           * numa logging to libcrun logging */
+          nodemask = numa_parse_nodestring_all (memory_policy->nodes);
+          if (! nodemask)
+            {
+              return crun_make_error (err, EINVAL, "numa_parse_nodestring_all validation failed");
+            }
+
+          ret = set_mempolicy (mpol_mode_flags, nodemask->maskp, nodemask->size - 1);
+          savederrno = errno;
+          numa_bitmask_free (nodemask);
+          errno = savederrno;
+        }
+      else
+        {
+          ret = set_mempolicy (mpol_mode, NULL, 0);
+        }
+
+      if (ret < 0)
+        {
+          return crun_make_error (err, errno, "set_mempolicy: %d errno: %d\n", ret, errno);
+        }
+    }
+  else
+    {
+      libcrun_debug ("no linux numa mempolicy configuration found");
+    }
+#endif
+  return ret;
+}

src/libcrun/mempolicy.h

@@ -0,0 +1,27 @@
+/*
+ * crun - OCI runtime written in C
+ *
+ * Copyright (C) 2017, 2018, 2019, 2021 Giuseppe Scrivano <[email protected]>
+ * crun is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation; either version 2.1 of the License, or
+ * (at your option) any later version.
+ *
+ * crun is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with crun.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef MEMPOLICY_H
+#define MEMPOLICY_H
+#include <config.h>
+#include "error.h"
+#include "container.h"
+#include "status.h"
+
+int libcrun_set_mempolicy (runtime_spec_schema_config_schema *def, libcrun_error_t *err);
+
+#endif

src/libcrun/mempolicy_internal.h

@@ -0,0 +1,60 @@
+/*
+ * crun - OCI runtime written in C
+ *
+ * Copyright (C) 2017, 2018, 2019, 2021 Giuseppe Scrivano <[email protected]>
+ * crun is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation; either version 2.1 of the License, or
+ * (at your option) any later version.
+ *
+ * crun is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with crun.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef MEMPOLICY_INTERNAL_H
+#define MEMPOLICY_INTERNAL_H
+
+#include <numaif.h>
+
+typedef struct
+{
+  const char *name;
+  int value;
+} str2int_map_t;
+
+/* update mpol_mode_map based on numaif.h MPOL_MAX
+ * the warn in mempolicy.c will indicate that an update is required.
+ * MPOL_WEIGHTED_INTERLEAVE has been introduced in MPOL_MAX 7 (kernel 6.9+)
+ * and some distros still has older kernel interfaces */
+str2int_map_t mpol_mode_map[] = {
+  { "MPOL_DEFAULT", MPOL_DEFAULT },
+  { "MPOL_PREFERRED", MPOL_PREFERRED },
+  { "MPOL_BIND", MPOL_BIND },
+  { "MPOL_INTERLEAVE", MPOL_INTERLEAVE },
+  { "MPOL_LOCAL", MPOL_LOCAL },
+  { "MPOL_PREFERRED_MANY", MPOL_PREFERRED_MANY },
+#ifdef MPOL_WEIGHTED_INTERLEAVE
+  { "MPOL_WEIGHTED_INTERLEAVE", MPOL_WEIGHTED_INTERLEAVE },
+#endif
+  { NULL, -1 }
+};
+
+/* flags cannot be tracked the same way as mode */
+str2int_map_t mpol_flag_map[] = {
+#ifdef MPOL_F_NUMA_BALANCING
+  { "MPOL_F_NUMA_BALANCING", MPOL_F_NUMA_BALANCING },
+#endif
+#ifdef MPOL_F_RELATIVE_NODES
+  { "MPOL_F_RELATIVE_NODES", MPOL_F_RELATIVE_NODES },
+#endif
+#ifdef MPOL_F_STATIC_NODES
+  { "MPOL_F_STATIC_NODES", MPOL_F_STATIC_NODES },
+#endif
+  { NULL, -1 }
+};
+
+#endif